[TYPO3-mvc] Integration of TYO3 Corefeatures in Extbase

[Philipp]

Hi,

some more questions: In my extension i make use of FAL. When i added the property into my Model and defined it as a ObjectStorage with subtype FileReference (or File - i tried both) it didnt work. So i had to write my own patch for that problem.

Now - i do also make use of the new Categories delivered with typo3. When i add the Property categories to my model and define it as a ObjectStorage with subtype Category 
\TYPO3\CMS\Extbase\Persistence\ObjectStorage<\TYPO3\CMS\Extbase\Domain\Model\Category>

Extbase displays an error.

So my first Question:
Is it possible to
a) make this anyway?
b) make matchings in the database based on this relation?

And my second Question:
Are you fucking kidding? Why do you implement such features into a stable release if it does not work? All of that costs massive time that no one can calculate! If a CMS or Framework features something i can expect it to work, dont i? Dont misunderstand me, i am very thankful for the whole package of typo3 but that sucks really bad. 

Please answer me on this, if the category system does not work i have to write my own - and i really would like NOT to do that.