The dual-booting laptop runs a clean WinME "98lited" install (Win95OSR2 explorer and shell), which is fast as hell, along with a XP Trust install for VST5.2 and access to LAN resources.
Just tried the "Cubase 3.x Key Authorization Compatibility Tool" from Steinberg, as found into the Library folder of the VST5 CDR.
https://www.proaudiosupport.com/a23260/cubase-vst-5.0-dongle.htmlSeems its intended purpose was to allow to run the VST3.5/3.7 with a VST5 blue LPT: dongle.
Or the oher way around, to run VST5 with a VST3.5/3.7 LPT: dongle (green or red, it's not specified).
It just swaps the Synso32.dll into C:\WINDOWS\SYSTEM\ from version 2.0.0.0 (142kB) to version 3.0.0.0 (120kB).
VST24 3.7 Synso32.dll is yet another one (135kB), and does not have any embedded version infos.
But not much luck either, VST3.7 won't run with the blue VST5 dongle.
And VST5 does not recognize the red VST24 dongle.
I understand why people are sticking to cracked versions, that also launches much faster without the dongle check.
USB eLicenser has an edge here, TBH.
Off-topic: weird config of yours with this forum. The left/right arrow keys don't move the cursor backward/forwoard into the text box as expected, but are bound to previous/next page of the web browser. It's a royal PITA when redacting posts here, if you ask me, unless there's a reason to this. 
see thread http://www.oldschooldaw.com/forums/index.php/topic,7730.0.html