I encountered a weird bug in my play through which happened several times, yet when I tried to recreate it, it was elusive.

basically what happened was that I had a large setup of atmospheric condensers creating nitrogen and copied it. Then I removed all the recipes from the condensers and tried to switch them to hydrogen, but that was impossible, because the pipes remained listed as containing nitrogen even though they did not nor were they connected to any buildings consuming or producing nitrogen. As a proof of concept, the pipes went back to normal when I deconstructed everything and then pressed ctrl Z, placing everything back in. I have screenshots but it doesn´t seem like I can post them here. I´m running multiple mods but the only ones that are listed under the buildings included in the build are Space exploration, Krastorio 2 and squeak through. Since krastorio 2 is the main mod acting on the condensers I figured this is either a vanilla bug or a k2 one.

I have only encountered this bug in large setups with hundreds of condensers, and even then it doesn´t always happen.

pipe often keep a little fluid in them this is not surprising and not specific to krastorio.

yeah, it´s just that I never turned power on, BUT it seems I accidentally did anyway on one of them causing just a tiny bit of nitrogen to enter the pipes.

All u have describe seem exactly an issue with the Factorio engine related to fluid and pipe, nothing relating to modding or this mod.

PS: u can post images here, see how Markdown syntax works.