So I have spent some time trying to figure out where and what the issues are
VMwre Host:XP
VMware Guest:XP
this works ok but you have to chage the adapter type to {DS9097E} (including the brackets)- for some reason it cannot find the DS90097U (despite that being the type of adapter plugged in) - see http://mango.serotoninsoftware.com/forum/posts/list/408.page
Downloaded the various Java exapmple scripts from Maxim - speifically FindiButtonsConsole.java which will walk thorough the adapters and then the ports on each adapter.
From lacing this with debug prints I conculded that it only likes the DS9097E device.
VMware Guest:Ubuntu
replicated the above - and could not get it to work at all - the port is detected as a "Serial comminication port" - but it could find my DS9097U - and could not work out that even setting it to DS9097E why it still did no work
Will be migrating the whole thing to a real Mini-itx platform shortly - and hope that the problems do not persist.