Hi Guilherme,
I have no idea why some of your system fonts are not appearing in the Nodebox menu. I am not a Windows user and know little about the intricacies of font installations. Do you see any common pattern in the fonts which are excluded?
I am adding Frederik in the faint hope he might have some insight.
Yes, selecting fonts from that tiny font list in the textpath node is MADDENING. This is a pet peeve of mine, not just in Nodebox, but everywhere. In almost any user interface, developers often give little thought to the width of an input field, typically leaving that width at the default value. The amount of human misery this causes, repeated millions of times every minute of every day all over the planet is mind boggling. Yet the developer could end this nightmare IN A FEW SECONDS by simply widening the damn field. There is almost always oodles of wasted space for the field to expand into. ARRG!
Anyway, if you are DESPERATE, I have attached a desperate solution.
You can use the font_table node from the Cartan Node Library to list all the fonts available to Nodebox and widen the display on the left to your heart's content (use data mode and widen both columns). You can then scroll down until you find the font you want, enter its index number into a slice node, lookup the font name from the table, and feed that into your textpath node. See screenshot for an example.
The font_table node does require an external Python library, font_table.py (included in zipped demo), so you will need to add that code library to your Nodebox file. And if you change the fonts in your system, the index number you entered may extract a different font, so you would have to keep an eye on that. And if you share your Nodebox file, anyone using it would retrieve a different font than what appears on your system.
So this technique is only useful for personal projects when you are desperate enough to go to this extra bother. But at least it's an option.
I suppose you could also try to figure out how to shorten the font names in your system. There is probably some way of doing that, but I would not recommend mucking about with things that may have far ranging effects elsewhere in your system.
Sorry I couldn't be of more help. If there are any font mavens out there with other suggestions, please jump in!
John