In the 1.7x version of the software there was a Sniper setting selector under the Performance & DPI tab. It's now gone in 1.8x.
First, please bring that setting back. It is nice to have a quick and easy place to edit it. (see Clipboard1)
Second, in the Actions Editor under DPI settings, there is a place to choose how you want the sniper mode to work, Toggle or While Pressed. (Clipboard2) I'd like to see that option added to the above mentioned setting.
In the last version of the software you could select the default Sniper mode from the list of available pre-defined Actions from the drop down. That feature is gone now in 1.8x; you now have to go into Remap Key/Button and Sniper is removed from the list.