Success!
I've installed 2.0.2. And as I see it has some good and bad things. One of the features that 2.0.2 has, and 3.1 don't is to show (and name) bugs. I mean in 3.1 you only get information 'error found' but it don't say what kind of. You have to guess by your own. Thanks to this i was informed by 2.0.2, what was
the reason of blank screens. It's simple: in both libraries you gave me, there are NO 'refresh', 'init' and 'show' commands. So i removed these line from the code and.. voila! It works.
Final solution:
1. Put cherepets's lib_keys.class file (474B ) inside "Libs" folder
2. Do NOT use .init, .show or .refresh commands.
3. Compile using 2.0.2 or 3.1 version of compilator.
Thanks both of you for help. You did a good thing. Thank you.