PVP-K30 (Polyvinylpyrrolidone, (C6H9NO)n) is used here as an adhesive.
This is what sticks things to your bed.
PVA (Polyvinyl alcohol, [-CH2CHOH-]n) is your release agent.
This helps parts pop off after you're done
PVP-K30 is just one option, and other K-values of PVP exist.
K refers to the molecular weight, or roughly how many molecules of PVP are chained together.
I've also seen PVP K15, K17, K25, K60, K90, and K120 for sale.
I have not personally tried different weights of PVP as an adhesive, although theoretically higher values will bond more strongly.
Alcohol here basically only exists to more easily dissolve the ingredients, and make the solution evaporate more quickly after application. Adjusting the ratio should not affect your glue much at all, beyond making it dry on the bed at different rates. If you find you need more time to apply, you can just increase the amount of water (I mix mine very strong, and dilute during application, so adjusting the ratio when applying just means I use a different ratio of water to alcohol during dilution)