Not sure if this is just me but i have tried the plugin on 3.8 and 3.16 with the latest update and getting the same issue. When trying to batch export to using composer image i receive a rather useless QGIS warning " Error : Image generation error: " the plugin runs through each layer but no images are generated.
I have tried simplifying the composer so it is just a map and i receive the same issue.
Additionally while sifting the log i found the following message which i suspect relates to producing shapefiles(?), though this is still working;
WARNING warning:C***/python/plugins\TomBio\biorecdialog.py:1201: DeprecationWarning: QgsVectorFileWriter.writeAsVectorFormat() is deprecated
error = QgsVectorFileWriter.writeAsVectorFormat(layer.getVectorLayer(), filePath, “utf-8”, outCRS, formatArg)