I have updated the By-me control unit software from version 1.1x to 2.00 and now I can't activate the burglar alarm.

Version 2.00 (and later) fundamentally changes the burglar alarm system logic by adding the concept of partitions. The moment you upgrade, the control unit does not allow activation of the SAI because some new information is required: partitions present (SAI zone sets) and partition association with various arming devices. When these parameters have been entered, the burglar alarm system will resume correct operation.