Fictional Trucking and Service Skin Pack 5.1

The mod functions without the paid mods installed, you just won't be able to use specifically the skins for the paid mods (In this case the Scout and Segra). If you want to, you can also delete the segra and euvan folders from the vehicles folder of this mod.

What is flying?

The Spearleaf containers seem to spawn ok for me. If you're talking about the T-Series flatbed config with the container on the back, you need the T-Series Drivetrain Expansion mod for the container to show up.
https://www.beamng.com/resources/t-series-drivetrain-expansion.29462/

Yeah it looks like the T-Series cargo box textures were changed in the 0.32 update. I'll have to fix that

The mod works fine without the Segra Ultimat, you just won't be able to use specifically the Segra skins. If necessary, you can delete the segra folder from the vehicles folder of the mod.

There are some skins from this mod in the Gavril Durham Official Skin Pack
https://beamng.com/resources/gavril-durham-official-skinpack.24787/

The rollback upfit skin textures don't currently work because the textures were changed in the BeamNG update. To fix the issue for now, open this mod's zip file, go to vehicles/common, and delete the folder named pickup from this common folder (do not delete the pickup folder in vehicles/pickup)
In the next update I will be removing the rollback upfit skins unless the skinnable rollback mod gets updated

Yeah I'm in the process of updating all my T-Series mods for the new remaster

It will be updated soon, but it may take a while to get everything fixed