This module was written to add a List of theorems to LyX.
To install the module, copy the file theorems-thmtools.module to the layouts folder in LyX's user directory (which can be found in Help->About LyX), and reconfigure lyx via Tools->Reconfigure.
See test_thmtools.lyx and test_thmtools.pdf.
GNU Affero GPL v3.0. See LICENSE.