The newly-uploaded experimental version (NeoLemmixEditor_V1.42n_1602161237) contains the proposed "Import Layout" feature (check under the Edit menu). It does not yet remove the old oddtabling. Give it a go and let me know what you think.
Note that I haven't yet tested it with SuperLemmini levels, but I did code it to hopefully work with it.
EDIT: Found a major bug with this feature; uploaded a new experimental version that fixes it. It also fixes the much-less-major issue that a popup message from testing / fixing during the layout import was still present.