Publicado originalmente por shuz:

How do you idle 30 games at the same time? i don't see that option on idlemaster, only idle games simultaneosly up to 2 hr.

If you start IM through the command line you can select a specific game, do that 30 times. Alternatively, have 30 games with drops remaining and less than 2 hours.

You could also start a game normaly, and use Alt+Tab back to the client and start another game, repeat this process till you have 30 games running.

Theres no benefit to doing so. Officially, running multiple games simultaneously hurts the rate you receive cards, but there have been reports that it completely prevents drops.

Have you tried running IM as Administrator?

Are you running multiple games at once? There have been mixed reports of it slowing drops to outright preventing them.

I'm seeing 3.4 hours, so hopefully the problem's resolved itself and Steam is now properly tracking your time.

Probably a coincidence. First I've heard of IM in relation to a problem common enough to warrant a Knowledge Base page
https://support.steampowered.com/kb_article.php?ref=2117-ilzv-2837

You should be able to enter the AppID manually

Start SAM
Double click on the games you want to idle.

1) Find the path to IDle Master.
2) Open command prompt/
enter
The path will be something ridiculous like

From the FAQ

Can Idle Master be used to pad my playtime of a particular game?

The steam-idle.exe application that's included with Idle Master can be given a command line argument of the appid of the game you'd like to idle. For example, if you'd like to idle Team Fortress 2 for playtime, you can simply run "steam-idle.exe 440" from a command prompt. There is no user interface for this, it must be done through the command line.

Steam can only track 30 games at a time, so unless you have 30 (or fewer games) you won't be able to do all your games at once.