Temper requires Windows XP SP2. An audio interface with an ASIO driver is required for VST and audio support. A three button mouse and MIDI keyboard or other controller is highly recommended.
Temper is available as unrestricted, unexpiring trialware. You are free to evaluate it for as long as you need, but if you decide to make it part of your workflow you're required to purchase a license.
(previous release: Temper 1.3.1)
UPDATE: Temper is no longer for sale. I've had very limited time to devote to development for awhile now so I've decided to end sales. It's still a product I personally use and will improve as time and interest warrants. I can't express enough how appreciative I am to everyone who's purchased this software over the years -- it's amazed me how generous people have been with software that is largely free to use. The few features that were available after purchasing a license -- note decor, group operations, performance time and the VST randomizer -- will remain exclusive as a thank you to all paying customers, but please enjoy the completely free and fully functional version that's still available.