1) Your Internet connection speed is fast enough (512kps)
3) You appear to be trying to use AI2, the standard compiler via your browser. Since you are using Windows, Chrome or Firefox browser are best. You cannot use Explorer. Explorer is incompatible with AI2.
4) Are you trying to use AI Classic? It is not clear from your post or are you trying to use one of the personal servers like AILiveComplete?
7) Be aware, that unlike Eclipse and Android Studio, AI2 does NOT require JAVA.
8) Frequently the easiest way to FIX AI2 is to delete the installed files ... they are probably here on your PC: C:\Program Files (x86)\AppInventor\ Use the uninstall.exe Then, restart your PC and follow the install instructions of AI2.
9) For most people, the online version of AI2 works very well. If you are having difficulty compiling, loading projects the issue may be your AI2 code issues and not necessarily your Internet speed.
Try some of the suggestions mentioned above. If you get working, please let us know. If you do not get working, tell us what you tried and someone will make more suggestions.
Regards,
Steve