before i installed -5 i backed up the -4 installation. i then copied everything starnet related in the old bin/ folder to the new bin/ folder, and likewise with the lib/ folder (the weights.)
starnet runs with no problem this way under -5. if there is a problem with gatekeeper i wouldn't see it because ostensibly the starnet dylib is already blessed. also i am way back on high sierra, so if there is a problem with newer versions of OSX i won't see that. i did compile the module on high sierra and at least up till now no one running 10.14 or 10.15 had problems installing and running starnet...
I followed the same procedure on Catalina 10.15.3 except did not save the "blessed" dylib. Instead, I installed a copy directly from the distribution. When attempting to install with Install Modules, Gatekeeper was triggered, but after approval StarNet was not installed, nor did Install Modules find it anymore in a recursive search. After observing this, I deleted everything and reproduced the same steps, achieving the same result.
Today, after seeing Rob's report, I tried for a third time using an already-blessed dylib. Everything acted the same as above, except this time the Install Modules did not find StarNet at all and no Gatekeeper notification was generated.
In all cases, PixInsight reports, "0 additional PixInsight module(s) were found on directory: /Applications/PixInsight/bin (Recursive search)". It is as if PixInsight thinks the module is installed, although it is not.
John