TL;DR Load removal won't work if your screen's vertical resolution isn't listed on the bottom of this post. HMU if you need it fixed for yours.
Currently the load remover script detects the "mission complete" screen by checking a certain memory address, which value depends on your screen's vertical resolution. There's no apparent logic to the values themselves which prevents me from doing a one-size-fits-all thing, so I bodged a solution by manually typing out the values for a couple most common resolutions.
Currently the loadremover supports the following vertical resolutions:
720p, 768p, 900p, 1080p, 1152p
Every other resolution will stop the timer on the "mission complete" screen, and will break the mission splitting.
If you wish for your resolution to be supported, first of all contact me over on Discord or through SRC's DMs. While that's worked on, please consider changing your resolution to a supported one (maybe you'll like it more!)