IE indeed tend to get me a lot of unstyled pages on first page load with CMS that store the stylesheets in the database (it did too with textpattern. I don’t know how, but this was solved a while ago...). If I reload the page it just end up loading the css (at last !).
(Edit: Susan’s pointer maybe explain why : "MSIE sent a different Accept header on "Refresh" and similar operations than it sent on initial retrieval. In fact, on refresh/reload it sent */*" ... interresting...)
The last website I build with MODx I had to switch from using CSS as Document to plain old static file for CSS, else IE required the reload of page to load the CSS (could have gone with an alternate stylesheet for IE but didn’t want to). It’s good that you mention this again because I have been meaning to confirm this with other users before I reported this in FlySpray. It’s plain annoying...
About some people having their css downloaded instead of loaded couldn’t it be their server settings ?
Once thing I’ll do is maybe use
HTTP Tracer to understand what the heck is going on with IE.
@Susan : I’ll try the suffix method you suggest, and thanks for the pointer interresting read !