Grrrr . . .
This is something Cakewalk needs to fix: when selecting all events and markers to slide forward or backward, there MUST be a means to move the entire set of tempo changes as well - otherwise - the whole set of tempo changes is off to the events/measures.
 
Grr . . . .

I recommend you submit a feature request for it.  They are in the process of some sort of additional set of updates, maybe this would get looked at.
 
It certainly seems like one should have the option to do this or not to do this, or maybe it should just follow the events.
 
I suppose it would depend on what is occurring in the project as to what should happen.
 
Bob Bone
 

pdarg
Grrrr . . .
This is something Cakewalk needs to fix: when selecting all events and markers to slide forward or backward, there MUST be a means to move the entire set of tempo changes as well - otherwise - the whole set of tempo changes is off to the events/measures.
 
Grr . . . .

Not exactly drag and drop but tempo changes are moved when using cut & paste although you may need to change your default options. Accessed by using Alt+Ctrl+X. Make sure the "tempo change" option is selected.
 
Alt+Ctrl+V gives you access to the paste options where you'll also find tempo changes.

Insert measures?

Yes, inserting measures will move EVERYTHING over - events, tempo changes, mete/key changes, automation envelopes