Hello Erik,
With standard TELEMAC-2D, it is not possible to use a moving punctual source. As told in the TELEMAC-2D user manual, "TELEMAC-2D will position a source at the closest mesh point to that specified by [the] keywords". There is an interpolation step, only done once as fixed sources are considered.
You can try to implement what you want, but be careful with the fact that the punctual source is to be defined at a node of the mesh, and depending on your mesh resolution, the paths of your moving sources may not be what you except.
For your 2nd question, with standard TELEMAC-2D the answer is no, except if you want to describe a region of sources (see feature associated to SOURCE REGIONS DATA FILE keyword).
Hope this helps,
Chi-Tuan