Dawgincontrol - When it comes to the "Soloists" tag what you are encountering/suffering from is the simple fact that some of MC's "; Delimited List" tags are set to auto-sort lists whose edit type is "List" before storing them in the database, i.e."Soloists", but not the ones whose edit type is set to "Standard", i.e. "Genre".
Since there is no way a TrackInfo Plugin can re-arrange the "Soloists in the order in which they perform", nor can a user change the "Edit Type" of a MC Provided Tag, all I can suggest is that you;
Add a prefix to the individual "Soloists Name" as a means of indicating the order in which they appear on the track;
or
Add a New Tag, with a "Data Type of List" and "Edit Type of Standard"; which would allow you to add/list the Individual Soloists in your preferred order
and then modify the TrackInfo Plugin you are using to display the Existing Soloists Tag and your New Tag or only your New Tag.
The only other way I can think of achieving what you would like to do is to modify the lyrics for every relevant track by inserting the Soloists Name in front of every group of lyrics they perform.
