If you're experiencing
-clipping through walls
-dying on platforms
-squishing or ducking meat boy
-inability to complete some levels and bosses due to timed objects
these are ALL caused by lag, you'll need to lower the detail of your game in order to fix them. here are the detail options, here is how!
Go to Library, then Right Click on Super Meat Boy and go to Properties

Click on Set Launch Options

Fill in the options starting with dashes and separated by spaces in the text field

-highdetail Highest detail
-meddetail Medium detail
-lowdetail Lowest detail
-ultralowdetail super horribly low detail
enjoy!

-Edmund