Any vinyl flooring is easier to cut when heated. You don't want to heat it so much that it expands in dimension. I used to install a pretty fair amount of vinyl but it is losing favor to other materials.
This is the way I would template a vinyl installation: Place red rosin paper on floor just inside any walls and protrusions around floor. Tape it down so it doesn't move. I usually cut it with a 1/2"- 1" space away from the wall, an accurate cut isn't needed. Using a compass with pencil, scribe around the wall and other surfaces placing a line 2" inward from the wall. Pull up the paper and tape onto new sheet goods. Using the same compass with the identical 2" spacing, scribe a line onto the vinyl. This should produce an accurate cut with no need for any trim.
It's also possible to trim the sheet in place by rough cutting and leaving an inch or two of extra material. The vinyl is then folded accurately at the wall-> floor joint with a stair tool and cut while in place. Trimming is a skill developed by doing a few installations.
BTW, nice job with the Allure.