First, the basic process of adjusting DSMLink for different injectors is simple. You simply use the ECU→Fuel dialog to adjust the global fuel slider and deadtime value. The Injector Data Compilation page contains a handy list of starting points to use. If you haven't already read that, please do so now. It contains a lot of information I just don't want to repeat here, like how to adjust those basic global fuel slider values for non-stock base fuel pressure.
Once you've made this basic adjustment, you can fine tune from there by watching fuel trims (LTFT) while idling and cruising. Again, the user's guide provides details on this process. Once idle and cruise are about where you want it, you can then focus on wide open throttle tuning by watching measured A/F ratio using a wideband and comparing against the estimated A/F Ratio provided by DSMLink. More details on the estimated A/F Ratio item can be found on the Estimated A/F Ratio page.
The current V1 and V2 2G offering only records the changes you make in battery-backed RAM. When the ECU loses battery power, the DSMLink settings reset back to whatever settings were specified on the original order form for that chip. You can, of course, always restore the ECU settings back to what you lasted save via the ECU→Load/Save menu. But, if you're making a large change to injectors on your car, you may want to contact us to request a new chip with settings that more closely match your new configuration.
None really, because the current V2 1G offering uses a memory board to permanently record the changes you make via the application. So even if you remove that 1G memory board and set it on your shelf for 10 years, it should still power up in an ECU with the same settings it had in it when it was removed. So there is no need for a new chip with new default settings in a 1G.