Hiya Doc,
Yes this PE3 works in 1.5
As for widescreen res's, In graphics options i scroll down to a highlighted bar that's a widescreen option (easy enough, then set other options as you want and accept)
I know i need a new card or 2 but i run mine in the graphics option @ 1920x1200
(gonna crossfire soon as later ati cards out
)
Have you tried the same game graphics settings as mine (mines the 8800gts 640 and mines fine (unless as now near land masses or mega action, but this is because i've gone from 1024 to 1920 res lol) your gtx should take to this game like duck to water lol
Don't try the editing though, just alter graphics similar to mine and check fps
Ahh how can you tell this from vanilla SH4/1.5
Well wait for a sunrise or sunset, And have a look at the colours/waves of the ocean
Vanilla SH4 the sea is a decent colour but lacks something, That something is PE3 and other mods lol
Ciao
Def