Seeking advice: shipsets in PBW

[Fyron]

Dogboy said:
I think he just selected them when he signed up for the game/ uploaded his empire file. I don't think he has the modified race pic/ship set/flag pic on his system, and this is probably the cause of the file error.

The shipset selected on PBW is purely for player convenience; it does not affect what shipset the game uses when it processes turns in any way.

Dogboy said:
Will this lead to substantially longer download times each turn, or does it just get installed and called up locally, with a pointer to different ship types being passed with each turn file?

Neither mod files nor shipset files are included in the savegame.