Interesting thread - I've just switched my GSG9 to the black rubber and deployant and had similar issues. The watch hasn't popped off, but it was difficult to figure out what went where, the instructions aren't great and yes the spring bars are all different. I found one spring bar much easier (although still lots of trial and error!) to fit, so I assumed I had it wrong at first.
So of waiting for it to pop off now! hideously tricky to fit the rubber to the case though!