See
JD install dir --> Edit file JDownloader2.vmoptions --> Change "Xmx" value.
Regaring filters:
Neither filters now views will just permanently remove items from your linkgrabber.
Also you're saying you've already added these items and probably do not want to re-add them to your linkgrabber (?)
In this case, the only thing that you can use "on the fly" if I remember correctly, are custom views.
Also, did you use filters or views here?
Please add screenshots of your filters.
If I understand, this is what you want to have:
Pictures
This is what you do not want to have:
Everything except pictures
If my assumption correct or did I mis-understood you?
I also thing you're doing it the wrong way - at least I would do it differently:
Filter (= hide) everyything that you do not want with a linkgrabber view --> Move everything you want from LinkGrabber to DownloadList --> Disable the filter again and check if you missed anything that you want to download --> If not, clear all items from your LinkGrabber
-psp-