Add Inn Variable visibility

wilk_u

Hello,
I wrote an add-in registered it in client add in table, got the key by sn.exe, it works fine, creates my .net control on page. But when I want to select it as a global variable on page to be able to use functions in it, I can't see it on .net tab in assemblies.
Does anybody know what can be the problem?

Edit: Answer is registering dll in GAC..