Prince -- Culprit in 911 Call ... He Promised Me Half a Mil

The floodgates have just opened ... a woman has filed a creditor's claim against Prince's estate, claiming the singer promised to richly reward her for providing the inspiration for one of his albums ... and she was involved in one of Prince's 911 emergencies.

Kimberly Felecia Potts claims in her legal docs, obtained by TMZ, Prince invited her to Paisley Park last year to officially reward her to the tune of $500,000 for creating the 2004 album, "Musicology."

Potts, who lives in Alabama, says Prince also wanted her to re-open the NPG Music Club -- a website launched back in 2001 but shut down in 2006.

We did some digging, and found back in January, cops responded to a 911 call for an intruder at Prince's estate, and found Potts at a side door. She told police Prince had called her for a job.