It is indeed based on XML tables. The only exception is the configuration file (ERA-Settings.conf) that allows some additional rule set customizations.
<salesman mode>
So... you want to add a skill? You can!
A new category? Yup.
Is it a new weapon category? No problem.
What about a whole new group of categories? Yes to all.
</salesman mode>
Now, the disclaimer. Advanced tweaking of the configuration files might cause the application to hang in the middle of character creation, or never finish starting up. But do not worry, this thread is here for those brave souls.
Second disclaimer. I have never played Spacemaster. So I made up some stuff and tested it, I can confirm the following works:
- Creating a new weapon category called "Energy". Just edit Categories.XML and add a line for it.
- Creating a new skill called "Piloting" in the Athletic category. You have to open Skills.XML, use as reference another skill such as Swimming.
- Creating a whole new group/category called "Stars" with a skill named "Planets". This is trickier. All categories belong to a group. If you have a group with only one category, you can give both the same name and ERA will compress it when presenting the character sheet. So first create a group named Stars in Groups.XML, then create a category with name="Stars" groupName="Stars" in Categories.XML. Finally edit Skills.XML to add a skill that will include groupName="Stars" categoryName="Stars" name="Planets". In the middle of all of this you will see that the related stats and table resolution can be specified.
- Creating a new profession named "Pilot". You can copy the example Fighter and go from there.
Disclaimer #3. Once you add new groups, categories and/or skills, it is very important to use, from then on, only professions that take them into consideration. Failing to include the cost for a new category or skill could cause it not to show up, or it could quit the ERA server unexpectedly.
This post is long enough as it is. Please let me know if something is not clear enough. Then let us know how it went!
As regards the NAS question: I have not tried it, I am not even sure what it might require. Remember that the demo is free, so you could try it and if you manage to do a nice setup and want to share it here, you're more than welcome.