Well, got it working finally... on my shared host there's a mod_security Apache module with restrictions set too high, resulting in the below XML error when trying to upload.
details: In the FCK window there's a bunch of frames, "uploadworker" is hidden but this is the frame that "catches" the upload. After unhiding this frame I received the following error:
Not Acceptable
An appropriate representation of the requested resource /mambots /editors /mostlyce/ jscripts /tiny_mce /filemanager /connectors /php /connector.php could not be found on this server.
(So naturally this is not a valid XML response!)
There are similar problems with Wordpress, PHPBB, vBulletin etc. so the fix is similar to the following, found here:
http://www.vbulletin.com/forum/showthread.php?t=167121:
1. create the following .htaccess file (or htaccess.txt):
<IfModule mod_security.c>
SecFilterEngine Off
SecFilterScanPOST Off
</IfModule>
2. put here: mambots/editors/mostlyce/jscripts/tiny_mce/filemanager/connectors/php/ (and rename to .htaccess if needed)
Incidentally everything appears to work with folder permissions at 755. Hope this helps someone.
