Well the topic names covers it all..
Basically this is my third installation of documentum, but I'll admit I'm no guru (i cover dfs/dfc usually) so if this question is silly, I ask for some forgiveness 
This being said, I installed documentum 6.7 64bit version on a windows 2008 enterprise 64bit machine with sql server 2008 enterprise 64bit..
All was well..
I loaded into the application server da and webtop.. apparently all is well, BUT!
see screen1.jpg..
If i try to create a document, I get an empty/greyed selection for the type of the new document! If by pure chance I want to try anyway without a set type, it warns me that the type cannot be null...
I cannot really point the source for an abnormality of this size!
Especially because if I circumvent the whole process using instead import, as seen in screen2.jpg I STILL cannot set a type,but i can move forward since it auto-recognize the formats, and then if i check the properties of the imported file after the whole thing, the file has a proper dm_document type...
Any advice?
I really can't pinpoint the possible source of the issue...
Thanks in advance,
Vitonofrio del Rosso