Although I'm wondering who might know this beyond the devs, because I'm not sure anyone on my friends list actually has Teleportation IV and Penpersonship (I tried to get these skills ASAP specifically for the usability of the Scripts).
I spoke to someone else who, like you, can also use their own scripts. So I filed a report and it'll hopefully get resolved. Thanks for the corroboration!
I just finished teleportation IV & there seems to be no script writing access for self or others. Also, there was no new quest which usually comes with completing a new skill.
The issue currently is that people who write teleportation scripts can use their own scripts only if they have any teleportation tokens. If you have 0 tokens attached to your account, it will not let you use your own script. Still haven't verified if having 0 tokens lets you use another persons script.
I believe it is not intended for the person who writes the script to use it, however, until they fix it, those who have tokens can spend energy to use their own scripts.