Hi Darren nice motor in the Garage!!
If you're having trouble running TvsT it could a huge number of reasons.
To improve in your case I'm sure all members have tips/advice but to give us a clue if you decide to try and improve, please publish your PC specs here; most crucially CPU type, GPU type/series, sound card (if any), RAM and software/OS.
You're wise to sit back and gather info though because you will probably be abe to tweak some settings yourself when you get confident.
And it won't be long because any man that that can file a Tiger from a solid block deservs great respect.
Silent Hunter 4 Gold is a good package at the moment (includes U Boat missions plus Pacific), with SH5 you need a permanent internet connection to play, and many posts critisize SH5 for not having the sim realism of the earlier series!
For what its worth Darren I am not qualified personally to criticise or praise the series as I don't own any SH games !! - but, I know a man who does!!!! Just some points maybe you might consider, apologies if you knew all this before.
Best Wishes - Mort