Matt;
Hi! Looks cool! I've always liked the rather intense and different look of the flakvierling - most guns come as single items, whether on carriages or mounts or in tank turrets (big ships are a rather select and special case), and this thing just shouts "concentrated blast"!
Never built one, other than that old Tamiya Wirbelwind, so cannot ID what-all some of the DML issues might have been... but one thing does come to mind: the front shield looks like it does not sit straight across the piece, but rather has a small amount of back-slant to either side. Is this the way it is supposed to go? I've built a few flak 38 by different manufacturers, and the shields on those sometimes cause problems getting them to sit straight across the mount - which they were in those guns - so I'm wondering if your fit is a similar issue, or if it is the "real" appeearance of the rig.
Just asking!
Cheers!
Bob