How can I combine the app from the wordpress, vtiger and ORTS iso's into one appliance?
IE install each appliance as it's own VM. If you wish to use bare metal then I can highly recommend ProxmoxVE (Debian based hypervisor OS).
Alternative short, easy answer: you can't.
Long answer: You could create your own custom appliance by using one as a base and adding the functionality of the others manually. If there is a TKLPatch available (eg vTiger) then you could use that to add the extra functionality but you will probably need to adjust a little (so you don't lose the original functionality).
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