If the footswitch connected to the DUAL CUBE BASS LX cannot be used to record with the looper, check the following points.
Mode and polarity switch settings for the footswitch
Set the footswitch mode and polarity switch as shown in the figures below.
FOOT SW CTRL ASSIGN
In the DUAL CUBE BASS LX Editor, go to SYSTEM, then FOOT SW CTRL ASSIGN, and select "LOOPER".