Opinions about Mac App Store and UCI user interface App?

[trojanfoe]

What are your opinions about the likelihood of seeing a UCI User Interface released via the Mac App Store, given the following condition (from here; Apple Developer account required):

2.15 Apps must be self-contained, single application installation bundles, and cannot install code or resources in shared locations

I believe that there is free access to non-shared locations such as:
~/Library/Application Support/MyGreatApp/

I recently verified that a sandboxed app can download a document to the directory above. [In a sandbox the path is in fact swizzled to something rather different.]

I expect that engines could be downloaded similarly, unless the Mac App Store restrictions go beyond sandboxing.

Sandboxing it yet another issue (or will it be Gatekeeper?).

I have discussed the issue of starting UCI engines on the Apple Developer Forums and the opinion seems to be that it will be OK as my App won't be doing the downloading and someone commented that their App also starts other processes without issue. Looks like there is no need to worry.

My App would allow UCI engines to exist anywhere in the filesystem and the user can just configure the path to the engine along with the other engine-related settings. ~/Library is hidden by default, so I wouldn't expect a user to have to copy engines into that directory.