Watch Face not installing or crashing for certain user/device

A user has reported that my watch face will not install on their device after I uploaded a recent update. The device is a Venu Sq. This is the only user who has reported this so far. Here is their description of the problem (and for some reason the forum text entry isn't doing return lines properly after I pasted this so I apologize that the text is run together a bit):


"When I go into garmin IQ to my watch faces I see Merlin24 listed under not installed. I select it and it says the install is queued. When I go into the garmin connect app and go to watch faces there, the Merlin24 comes up under uninstalled. I select it and select “install” but then nothing happens, a spinner just spins on the screen."

Has this ever happened to anyone else?

The app is Merlin24. The code is nearly identical to a similar watch face Merlin which has a few extra features. The user says Merlin can install fine.
I wonder if it is related to a mysterious "Failed invoking <symbol>" error that I sometimes (but not always) receive at the end of a makeWebRequest() function. This only happens for Merlin24 and not Merlin. In the simulator, there is nothing listed for the stack; I only know where it occurs based on a couple of println statements.
There is another user with an Approach S60 who says they can install Merlin24 but the app crashes when they try to enable OpenWeatherMap as the temperature setting (which is the only setting that uses the makeWebRequest() function). They sent the CIQ_LOG.txt file and I realized I did not call Toybox.Position in one of my files for both Merlin and Merlin24. (But why did Merlin still work and why have only a couple of users had issues?) After fixing that, the app still crashes for this user with the Approach S60, and I still see the error in the simulator, and the user with the Venu Sq still cannot install. I am waiting for the Approach S60 user to send the log file again. Similar to the other problem, this is the only user who has reported the app crashing.
Any clues as to what might be going on?