I'm one of the Junior Mods on locostusa, and looking at your post here, I think the problem may be that locostusa.com's web site is a fair bit older, and less sophisticated, than usa7s.net.
When I looked at image info here for a typical photo submission of yours (I used the pic with the two mag wheels) I found...
4,032px × 2,268px (scaled to 1,000px × 563px)
...where on locostusa it's just 4,032px × 2,268px, so your photos take up a little more than sixteen times the screen area on that site than they do here. It's a pretty old site, a couple decades, and that, plus locostusa not having a $20/yr membership fee, means it's not as technically sophisticated as USA7s, so much like Locost builders, LocostUSA users have to do a lot of the work themselves; in this case, shrinking their images down to a viewable size.