Subtitles cause burning app to stop processing

[freddy3333]

When using EncodeGUI 1.2.3 to add HDR to .m2ts or .mkv movie files WITH English subtitles, I get errors

....or EncodeGUI completes with a "Fail"; or, if EncodeGUI does complete, the program I'm using to burn the HDR'd .mkv (or .mp4 or .mov, etc.) to a blank blu ray disc (DVDFab 12) just stops processing somewhere along the way (it doesn't freeze or crash, it just stops processing - the CPU activity goes to "0" and its time remaining counter stops counting down & begins counting up. Then, after ~ 20 minutes, the time remaining counter goes to "0.00" and remains there. The app is otherwise functional - I can pause, cancel or close it without issue, but it just stops processing whenever I use it with a subtitled video file outputted from EncodeGUI (the same file w/o EncodeGUI-encoding works fine also). However, if I process the same video file WITHOUT subtitles, DVDFab processes it onto blu-ray just fine.

I've tried with the Encoding option on the Subtitle tab enabled and disabled, but no difference. I've tried outputting from EncodeGUI as .mkv, .mp4, .mov and .ts, but with the same results. I've tried on three PCs, but, again, same results. I've tried setting Subtitles to Passthrough, Auto Encode and Encode, but I've yet to get any of them to work properly.
Am I setting something wrong, or is there something else I need to do to use subtitles?

• CPU: AMD Ryzen 9 5950X or AMD Ryzen 9 5900X or AMD Ryzen 5 5600X
• GPU: RX570 4G or RTX3060Ti 8G (with latest drivers)
• RAM (amount in GB): 64G or 36G
• OS (AND version): Windows Server 2019 (latest) or Windows 11 (latest)

[freddy3333]

I thought I'd attached the two log files to my previous post, but I don't see the .zip, so I'm adding them here.
EncodeGUI.zip