Regarding your questions…
1) The best route in my humble opinion would be to use a git repository so you can easily pull the environment files, nodes, scritps, etc… in one convenient way and allow for super-easy updates. Check qLib for how it has been done with Houdini, very very nice approach.
2) Regarding manipulations, I am not sure if there is a way to do what you want in its current form, my suggestion is to write support, they do listen way more than you would imagine.
hope it helps
BTW. The scale may be an issue… you really will want to review it on 1 unit = 1 meter. (my 2 cents)
Thanks for your time.
I'm keeping it on my site [matkovic.com], together with SI version. In one year, feedback was close to zero. As far as I know, significant majority of users of that system are not Houdini users, today. So, generally, I've decided to move on and start something completely new, while I'm not completely sure, where and when that new thing is expected to appear. System itself is really old, last conceptual change belongs to 2011.
Regarding writing to support or git, that's somehow out of my Houdini Indie level of engagement. It's pleasure, not business. If something doesn't fit in certain software, I'll take look into another one, there are nice and affordable choices around.
By the way, in ICE times, versions were not backward compatible, I've considered ‘too much of compatibility’ as an unacceptable limitation. It was only ICE as ‘compatibility holder’.