1. For the new system rinse the carbon blocks, then, rinse the RO membrane, finally, rinse the DI until the TDS meter shows 0 tds at the final product. Having an inline tds meter after the RO membrane and after the DI is the best way to verify that you have rinsed enough at each stage... you are trying not to foul the downstream module with the carbon powder and other factory gunk of each new component.
2. Tell us about your water making. Are you going to just make a batch once per month... or make a little every day? Are you going to leave it hooked up to the water supply, or just take it on and off?
Each time the membrane starts up after sitting for awhile... it will spill some dissolved solids into the DI resin. On your linline tds meter... it will come out of the RO membrane at say... 14 tds, and then after a few minutes drop to something like 1 to 4 tds. No big deal... but, if you dump this before it hits your DI, your DI will last longer. In this vein, it is better to make large batches on long continuous runs, versus lots of small batches of water. Some people will create a manual DI bypass to use when the RO membrane starts up.
I am not sure what to do if you unhook or system from the tap between uses. I am guessing you could just put in some shutoffs to keep it wet??