This is kinda concerning then - I extensively tested all possible HTLed ships for collision errors months ago and fixed the ones that issues appeared on. The Serapis was among those I tested, but I found absolutely no evidence of any problems with ramming and shooting from all angles.
If I've managed to miss an issue as large as the ones reported here on the Serapis, it makes me wonder what else might have slipped through.
From FSU internal, this is the list I've been keeping of collision errors. Has anyone experienced errors with the crossed out ships on the 'possibly broken' section other than the Serapis? We need to smite these errors for the next release.
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List of broken ships:
Aten (Rebuild completed)
Apollo (Not looked into this yet, but it's reported in the main forum thread that it's ghosting)
Hecate (Fixed in "FixedPofs1.0)
Faustus (Fixed in "FixedPofs1.0)
Sobek (Fixed in "FixedPofs1.0)
Dis (Fixed in "FixedPofs1.0)
SAC3 (Fixed in "FixedPofs1.0)
Zephyrus Not worth the huge effort involved in fixing for now. 
List of possibly broken ships: (ie, stuff that was converted with the pof exporter. Most I think are fine, but I'll check them out.)
UrsaPegassus (Slight ghosting on the tip of the nose but otherwise ok)
Amazon SatisAnuketMaraAresErinyesPerseusMjolnirSerapisMedusa===============