1) I have no idea.
2) I have no idea, this is what was alluded to in an email I received from Mantis. It was said to be a problem with FSPort, not the SCP. I believe it was Taylor (I deleted the email last night) who responded, and said that FSPort has a specified model for the Taranis.
3) Sorry, I read this awhile back and misremembered it.
We've abandoned the attempt to keep the Port compatible with the main FreeSpace 2 campaign (considering the now-common use of the -mod feature and the fact that several ship stats changed between FS1 and FS2) and turned it into its own separate mod.
Please understand that I'm not talking about all Cain/Lilith class ships, but only the Taranis specifically.
I took a screen shot (which I included in the Mantis report, but deleted after) of the Taranis while it was being towed away because I noticed it looked particularly ugly. I didn't submit the report until I was playing the Playing Judas mission, where you had to scan the two Cain class cruisers. It was here that I noticed "hey, those ships have an engine glow," and I looked at my screen shot of the Taranis to see that it only had a flat texture that changed in intensity to represent its engines.
No, I have no unofficial mod packs installed, everything is from Turey's installer, with the exception of the .mve's and sounds, which I took from my FreeSpace 1.
fs2_open_3_6_9.exe -mod fsport,mediavps -spec -glow -env -jpgtga -mipmap -2d_poof -missile_lighting -3dwarp -warp_flash -snd_preload