Hi JD.
I havent done this myself, what Micros version are you using? Version 4.3 onwards use Table Management (TMS, and its a feature of this to enable Web interaction via DLLs used in Powerpoint (of all things).
Printing in Micros (for POS not PC) depends on the MDSPRINTHOSTS.xml file stored in the \Common\ETC directory (its like an INI and is used by clients)
MDSPrinting.dll has an Execute function (its only IfC) that calls IMDSService (ISAPIMDSSERVICE.dll). My registry has it sitting in:
C:\inetpub\Scripts\ISAPIMDSService.dll
strSessionKey, strMethodName, strXMLIn, strXMLOut
Its a tough one, all the printing done by workstations is handled in C:\Program Files\MICROS\Res\Pos\Bin, these DLLs are written in Visual C++ and I cant browse the COM interfaces...