Hi Fred Searing,
Not compatible with 8.81 version.
1.9.1 version compatible with following version
SAP Business One 8.82 PL12
SAP Business One 9.0 PL04
SAP Business One 9.0, version for SAP HANA PL00
SAP Business One OnDemand 1.0 SP02
Thanks & Regards,
Nagarajan