I've recently bought a bowl chastity device and found it one of the most comfortable to date, although I do wear it with tight briefs to help keep it close to the body. Like you, I have big problems with growth between most devices and the body pushing the device and the balls away from the body with severe pain.

The great thing about the bowl chastity device is that the balls are cupped by the device and cannot be pushed away from the ring, even if there is plenty of slack in the scrotum.

A word of caution when buying, there are two sizes marked as Standard and Large. Ball size is critical as they need to be contained within the bowl and in my view the two sizes should be relabelled as Microball and Standard.

I bought from AliExpress and I can't see that at the moment but they are on ebay at https://www.ebay.co.uk/itm/362939971736

I normally keep a used handwash liquid bottle next to the toilet, which I fill with a mixture of liquid soap and warm water, then, whilst I'm sitting on the toilet, use the pump to spray it liberally wherever it will go.

I've had all kinds of pains with ball trap devices, so much so that in general, I have purchased real chastity belts, where the strain is taken by a belt around the waist rather than the testicles. The problem is that these devices are more difficult to buy, more expensive and bulkier to wear and store.

Recently though, I've been having some success by strapping the ball trap ring firmly to the groin, so it doesn't put strain on the balls. I have one strap which passes through the ring at the bottom and then goes between my legs and encircles the waist around my belly button, and another which passes through the ring at the top and encircles the waist to the rear. Keep those tight and the device is kept next to the groin, with no tension on the balls.

It's still a bit experimental, but it seems the only discomfort I'm getting now is the normal natural discomfort when I try to get hard.

I find devices with a strap around the waist and then a tube between the legs such as the one below are significantly better. The morning woody becomes a discomfort, rather than total agony. They seemed to have gone up considerably in price recently. I paid about £35 about six months ago.

https://www.aliexpress.com/item/32890854910.html?spm=a2g0o.productlist.0.0.635860d8V6xqwZ&algo_pvid=84942e5a-1167-4fd5-88ed-a85ef0a9c060&algo_expid=84942e5a-1167-4fd5-88ed-a85ef0a9c060-23&btsid=2100bdde16194520502658257ef4af&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_

I’ve had the same problem in the last day. My iPhone software is iOS 14.3. This problem appears the same as has also appeared in a separate blog with Android.

I was mostly finding that the app took a long time to download after opening, with the padlock and the spinning updating symbol, and then the app closed before it could get the download. On one occasion, it managed to get to the main screen and closed down a few seconds later.

I managed to fix it by rebooting phone, but it has left me a little nervous about the reliability.

Until now, I’ve been using an 8-digit combination to set a 4-digit key safe – setting the first 4-digits of the combination directly on the dials, and then adding the second 4-digits to modify the first. The problem is that a sticking dial may sometimes mean I miscount the modifier and incorrectly enter the combination, with unpleasant results. I have now started using a method which looks complex at first, but is all about a methodical approach. Others may find it useful.
 
I request a 12-digit combination for my 4-digit safe, and then scan through it, looking for the numbers 1-4, representing the four dials on my safe. I set the number immediately following that number on the dial. So, for example, if the digit 3 is followed by 7 in the combination, I would set dial 3 to 7.

The following examples show how I set the safe, always ensuring that my thumbs obscure the dials other than the dial I am setting, so I can only ever see the dial I am setting:

Combination 839802780964   
The first of the digits 1-4 is 3, immediately followed by 9, so I set dial 3 to 9.
The next of the digits 1-4 is 2 followed by 7, so I set dial 2 to 7.
The third of the 1-4 digits is 4 at the end, so I continue the series back to the beginning and set dial 4 to 8.
Digit 1 does not appear in the 12-digit number, so I search for overflow digits 5, 6, 7, etc. In this case, there’s no 5 in the combination but I find 6 followed by 4, so I set dial 1 to 4.

Combination 041370042942
Dial 4 is set to 1; (subsequent 4s are ignored)
Dial 1 is set to 3;
Dial 3 is set to 7;
Dial 2 is set to 9 (ignoring subsequent 2)

Combination 966037268789
Dial 3 is set to 7;
Dial 2 is set to 6;
Digit 1 doesn’t appear so I look for 5 (none present) and then 6 and set dial 1 to 6;
Digit 4 doesn’t appear so I look for a second appearance of 6 and set dial 4 to 0.

This seems intricate at first, but I’ve quickly gotten used to it and it seems easier and less prone to errors than my previous system.

I had the same problem which I solved by requesting an 8 digit combination. Set the first four digits on the lock, then turn the lock around so the digits are upside down, and what was the left hand wheel is now on the right. Now use the last four digits as a modifier to the number already set, doing it mainly by feel, and ensuring your fingers obscure the numbers.

More recently, I’ve found that turning on the sound as the distracting numbers are displayed is as effective.

I started off trying several cages and always had the same problem. When I got the morning woody as I lay in bed asleep, the body was warm, the testicles were slack and there was always a gap between the device and my body. That is where my erection grew, pushing the cage further and further away from my body to the point where my erection was trying to tear my balls from my body - excruciating pain.

I then bought a belt, similar to the one shown here on Ali Express:
 https://www.aliexpress.com/item/33051766195.html?spm=a2g0o.productlist.0.0.50401b3fXP26sI&algo_pvid=60015990-eeb4-4fe1-96a0-3345e4f87889&algo_expid=60015990-eeb4-4fe1-96a0-3345e4f87889-38&btsid=0b0a050116008667332377463eb5d8&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_

Now the waist band takes the strain of controlling my erection, not my testicles. Attempted erections, including the morning woody, are a bit uncomfortable rather than painful.

After urinating, I have a hand wash bottle filled with soapy water which I spray into and around the area. It works fine  although I've never tried more than 24 hour stints