Eric,
I am by no means an expert on the MailTo syntax, but I do have notes I saved for myself. This should get you going. The following should be in a formula rich text field:
var text Subject = 
    "Enter Subject Line Text here " & [Add Fields If Desired] ;
 
var text File = URLRoot() & "up/" & Dbid() & "/a/r" & [Record ID#] & "/e57/v0"; //use this if you want to include a file link
var text Body = 
     URLEncode("Enter text for body here")
    & "%0A%0A"   //THIS IS A LINE BREAK PLUS SKIPS A LINE
    & URLEncode("Company Name: " & [Company Name]) // EXAMPLE OF HOW TO ENTER TEXT AND A FIELD
    & "%0D%0A"   //THIS IS A LINE BREAK, DOES NOT SKIP A LINE
    & URLEncode("File Link: " & $File)
    & "%0A%0A"
    & URLEncode("QuickBase Link: " & [Link Field]));
var text Email = "mailto:Fakename@fakeemail.com" //WHAT EMAILS ARE IN THE TO LINE
& "?cc=fakenametwo@fakeemail.com"  //EMAILS IN THE CC LINE
& "&subject=" & URLEncode($Subject)    //NOTE: If you remove the cc line, then add a ? ie: & "?subject=" & URLEncode($Subject)       
& "&body=" & $Body;                                 
//Final Note: The first line after mail to should have a '?' and NO "&". This indicates everything following is being set.
  
"<a href="
 & $Email
 & ">" & "Create Email" & "</a>"
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Mike Tamoush
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