Ray,
I am always happy to have new sources of information; no offense taken. Sources often disagree, for a variety of reasons. I used Nafziger's "Poles and Saxons of the Napoleonic Wars" and Rawkins revised "Army of the Duchy of Warsaw" as sources. Nafziger is vague or lacks information on several of these details. Rawkins, however, has many details of individual unit idiosyncrasies, and is likely more up to date, Nafziger's work dating back to 1991 when access to sources in Poland was still limited. Of course, these units dress varied over time and with changes in colonel, etc, especially the minor details.
In reviewing Rawkins in detail, you are correct about the gold/brass chin scales and shabraque edging (officers), those were my errors and I will probably correct them, as they are easily changed. along with the brass edging to the peak.
The seams you are correct about the (plain) yellow, but (as discussed in the blog post) I intentionally added the red edging anyway, as I just like the look of it better (call it the colonel's whim!).
Rawkins specifically states that (in 1812, may have been different in other years) the 3rd, 7th, 12th, and the Lithuanian regts (17 – 21) had white sheepskins for the troopers in place of the black more commonly used by the other regiments. He of course could be wrong, or it may have varied by year. Either way, nothing I'm going to fret about.
The white lace band between the peak and the box I opted not to paint in, as it is largely obscured by the (white) cords anyway.
Neither source mentions the substitution of black girth for the officers in place of the white of the troopers, but Rawkins includes a Chelminski plate, which on close inspection does seem to show these in black for the officer, so you are doubtless correct on that point,. I will probably go back and correct that, as it is easily done and is is an interesting variance.
Rawkins mentions quite a few variations of epaulette colors for various regiment's center and elite companies, but not the yellow for this regiment. Again, this may be due to lack of access to that information, and/or variation from year to year. I most likely won't change those. Likewise the aigrettes of the Elite company were left at the depot on this particular occasion! :-)
Thanks again for the corrections and additional information.