For anyone running the game under emulation using FS-UAE with "Zoom" option set to "Auto", the screen size may seem quirky when transitioning or viewing maps.
To fix this you can add the following option in your FS-UAE configuration to keep a steady viewport during the auto-zoom transitions.
viewport= 74 * 640 * => 74 36 640 512, 106 * 576 * => 106 36 576 512
So far I only found 2 in-game resolutions that required this and adjusted them for Auto-Zoom, if I spot another strange effect I will adjust the row above with new setting.
I have also included this settings in the game configuration of AmigaLive (which is a front-end for FS-UAE)
PS. This setting is exclusive for FS-UAE series 3.x.x so please dont ask me for other emulators as I unfamiliar, they may have a similar option with using a different syntax or not require this option at all.