In response to your questions above, you're right, the original SP-300 requires a special "dongle" version of VersaWorks, which was $995, it's been long discontinued and is not available for sell any longer. If you don't have that dongle version, then don't waste your time, Roland does not have a method to get it working on Windows 7, 8 or 10.
For #2, Roland does not have a "conversion" to make the SP-300 turn into a different model. The dongle version of VersaWorks does not do this. It involves changes to the printer's main board (not recommended). Doing so is an unauthorized process and completely not supported by Roland. We'll let you continue investigating that on your own.
Take care,
Roland Technical Support
Roland DGA Corp.
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