After a long frustrating battle trying everything and with a host that doesnt allow lowering security with .htaccess with mod security turned off for async upload, I finally, yes, finally found the solution for me! Now http://www.ordne.no works like a dream, I can upload everything!
The ANGEL with this soultion is here:
This fix really fixes everything!
I hope a lot of frustrated souls in this community reads this post and send the angel mentioned a warm thought!