Running waterfall, plumes from external boosters are distant from the nozzle

[VulcanRidr]

Greetings all,

I am running KSP1, version 1.12.4 on linux, and have a number (approximately 60) of mostly visual mods, plus dependencies. My modlist is available at https://controlc.com/8587d8e6

I have noticed that, if I build a rocket with external boosters, the booster flame plume is multiple feet (in game terms) beneath the engine bell. Please see screencaps of a launch, with the boosters running, then jettisoned and just the main engine running, which is at https://imgur.com/a/h0HFaaC. Please note that this is the same launch...I took a screenshot, then staged the boosters and took another screenshot.

Okay...It appears that (at least on this rocket), it is specific to the Reliant engine. The inline engine on the spacecraft is a Swivel, but the 4 boosters are each Reliants. I switched two of them, as a test, to the Swivel, and the visual anomaly is not in fact there. However, the Swivel's lower thrust isn't quite enough to get me to orbit, unless I want to stick another pair on it...

Does anyone have any idea where in the configs to tweak?

Thanks,

--vr

Edited March 11, 2023 by VulcanRidr
Updated information about the problem.