"autostart" properly applies VRDP ports from machines.conf file, however the "start" command does not do this, but uses the default 3389 instead.
This is confusing to me, but as mentioned; this might be the desired behaviour to use port from VM config instead of from machines.conf
Yes , this is desired behaviour. I agree, it's a little confusing, so maybe it's better to apply the vrdp-setting also in the start command. If you would like this, you can enter a feature request for this, than I'll sort/work this out.