TL;DR Direct link to the overview of this ongoing epic saga: tinyurl.com/yr26r3zt
The position in the author list doesn't affect word/paper weighting. It would be difficult to generalize this because the meaning of an author's position in a list will vary by discipline. It might be feasible to filter on first/last-author papers but this would cause a much sparser input
Weighting of words from each publication/title is equal. At one point I experimented with a scaling approach that weighted by the number of citations the paper had but it was difficult to generalize and highly cited papers tended to cause a very small number of dominant words.
Svante Paabo
Looks very familiar
You can tweak that in the settings by reducing the maximum word count
I'm curious what was causing this in case something could be changed to avoid other users encountering the same issue. Did you get any error messages? Feel free to contact me directly with more information.