zracer.z5 and cursor position values with frotz

[BroadcastGames]

I cited frotz because I have that on Ubuntu 16.10 x64 desktop for comparison. It positions the cursor correctly using frotz's native interpreter on my desktop (not using RemGlk). Data file here: http://ifdb.tads.org/viewgame?id=tnljfhvnzvybysqt

Binding to RemGlk frotz produces values out of range. I've also tried nitfol and bocfel and they produce different results but also don't seem correct.

Here is the Init I'm passing to RemGlk:

{ "type": "init", "gen": 0, "metrics": { "width":120, "height":28 }, "support": [ "timer", "hyperlinks" ] }

Here is the input xpos/ypos I'm seeing out of range:

{"id":36, "gen":1, "type":"char", "xpos":85, "ypos":19 }
{"id":36, "gen":2, "type":"char", "xpos":32767, "ypos":65534 }
{"id":36, "gen":3, "type":"char", "xpos":32767, "ypos":65534 }
{"id":36, "gen":4, "type":"char", "xpos":32767, "ypos":65534 }
{"id":36, "gen":5, "type":"char", "xpos":32767, "ypos":65534 }
{"id":36, "gen":6, "type":"char", "xpos":32767, "ypos":65534 }
{"id":36, "gen":7, "type":"char", "xpos":32767, "ypos":65534 }
{"id":36, "gen":8, "type":"char", "xpos":32767, "ypos":65534 }
{"id":36, "gen":9, "type":"char", "xpos":32767, "ypos":65534 }
{"id":36, "gen":10, "type":"char", "xpos":32767, "ypos":65534 }
{"id":36, "gen":11, "type":"char", "xpos":32767, "ypos":65534 }
{"id":36, "gen":12, "type":"char", "xpos":32767, "ypos":65534 }
{"id":36, "gen":13, "type":"char", "xpos":32767, "ypos":65534 }
{"id":36, "gen":14, "type":"char", "xpos":32767, "ypos":65534 }
{"id":36, "gen":15, "type":"char", "xpos":51, "ypos":4 }
{"id":36, "gen":16, "type":"char", "xpos":32767, "ypos":65534 }

This is on the opening screen of zracer.z5, you have to keep feeding it glk timer events to keep it going. It will dance the cursor around.

It's possible it could be some 64bit issue on ARM CPU or something (running on Android) those 65534 and 32767 values look a lot like a short value underflow/overflow. I don't have a way to feed the timer events into RemGlk on my desktop to test Remglk naively on Ubuntu. Maybe we can come up with a small python script to feed RemGlk the Glk timer input every update generation for the sake of testing?

[BroadcastGames]

I found Glulx story that positions the cursor. The "The Wilds Of Orkney.gblorb" story, attached inside zip.
The Wilds Of Orkney_gblorb.zip