Unable to forward local key combinations to remote machine

I use the program AutoHotKey to create keyboard shortcuts in windows. One of my uses is to enable vim-like keyboard navigation globally. For example, while holding the alt key, pressing j moves the cursor left (alt+j is remapped to the left arrow), pressing l moves the cursor right (alt+l is remapped to right arrow), i moves up, k moves down, etc. This works perfectly on the machine directly. However, when attempting this over the Splashtop remote session, the shortcut (e.g. alt+j) executes once, then the alt immediately releases even as I continue to hold it down, and I get a stream of js. I have tried this with a combination of scenarios including with the ahk script running on my local machine only (in which case only the native (rather than the remapped) key combination is registered on the remote machine), on the remote machine only, and on both machines. I have tried all combinations of related settings including Keyboard Mapping = Alternative Mapping, Splashtop Mapping, and the options under "Keyboard Shortcuts". Currently I have no options checked under "Keyboard Shortcuts" and the issue is still occurring.

TeamViewer has an option to "forward keyboard shortcuts to remote machine". When I run the ahk script on my local machine and use TeamViewer with that option enabled, this issue does not occur. I assume this is because TeamViewer forwards the *remapped* key combination with that option checked, instead of the native key combination.  I must assume there is value in such a feature beyond my specific use case, or TeamViewer wouldn't have implemented it. Therefore, please implement this feature/functionality in Splashtop!