Try build 29 (already uploaded) and let me know if it solves your IDE file open issue.
I'm not sure exactly what you're trying to do with the xxx-F3 keys. A Ctrl-F3 should search for the next occurrence of the word at the current cursor. An F3 would then look for the following occurrence(s), and a Shift-F3 will look for the previous ones. That works here; if it's not working for you then please let me know the exact sequence of keys you're using. (Note that the xx-F3 key sequences have nothing to do with the Edit / Find function.)