@ Kruuger: I have always had the problem with F2 using AutoCAD and using ZWCAD. When running the vanilla program there is no problem but when loading certain .lsp & .arx/.zrx files the problem seems to appear. I have no clue why this happens.
I found out (in my situation at least) that when you only see the commandline (the F2 textfield) as minimized: press shift + right click on it in the F2 screen in the taskbar. THen it will show.