The problem with your WiiFlow cache that you pointed out was due to a single game, how about you delete it, rebuild your cache then see if wiiflow still crashes while building the cache for that game, if WiiFlow works as normal then more than likely it may be a corrupt .wbfs header and WiiFlow isn't handling it properly.
The best way to fix a problem when using beta's is to have tools to debug what your beta testing, e.g USB Gecko would help a lot. No need creating mass thread about different things, getting people to show you how its done.
Has anyone else reported the same error or is it just you?
Did you self compile WiiFlow or is is a pre compiled .dol ?
Self compile - if so, are you using the correct lib versions, are all source files intact.......
Pre compiled - make sure the .dol hasn't been corrupted during download........