I have a fresh copy of RW 7.51 running on my Mac Mini with new install (reformatted SSD with no user migration) of the latest High Sierra 10.12.6 (16G29). I took this steps to provide a totally clean fresh copy of OS and clean fresh copy of RW (downloaded from RealMacSoftware). I added in my Yourhead plugins (latest from their website too) and only some of my Stacks.
Problem #1 Some of icons in my RW Library are not showing up - just the text names. It is random across various Stack developers.
Problem #2 Some of Stacks I have installed are not appearing in RW Library.
When I load an existing RW Project, it tells me that the Stack is missing when it is in the RW Stacks Addon folder.
What I have done to fix the problem without success
I have installed Stacks both via RW and manually. All stacks were freshly downloaded from each developer.
I have removed and reinstalled those problem Stacks and still the problem remains.
Any ideas anyone ???