PG_Admin 4 V3.0 Launch Crash

Dear decent human beeings,

i was using v2.1 up until now just fine, but ran into the following problem with it, leading to the problem following the following problem..

I am using other software for viewing/editing (GIS)Data, and some kind of crash created a partial mirrored entry in a table , and now i can't seem to edit that table anymore.

Since it copied the id i used as pk, but did not use the same internal object-category-id when it created that false entry,

i switched the pk to a composite pk consisting of both entries, eliminating some trouble, but i still cant delete that entry, and it's messing (atleast it seems to be the reason) with the behaviour of the table , concerning editing in general. After checking everything else i found on the internet, regarding possible solutions, i found a snippet, from the mailing-list, talking about some small patch, created at the end of march, regarding delete issues with composite primary keys. so i checked the date of the version, and noticed 3.0 as a release after this patch, so i thought it might contain it, and solve my problem.

Deinstalled the old Version, applied the new one, and.. it just crashes without error. First time i start it i atleast see the small loading window, which cancels, and tries to open the browser on localhost (http://127.0.0.1:52147/?key=4fd5118b-4902-4e3e-8f75-14d052511022). subsequent efforts directly re-open the non-existent site in the browser.

Played arround with compatibility, and starting as admin and stuff, but im out of ideas. Happening on Win10-64, running postgresql with the postgis mod.

Hope i supplied all the necessary initial information, and thank you all in advance.