Can I combine weeks (like a short week and a long week)?

Not directly, but there is a workaround.

Commissioners can manually combine weeks by keeping the match-ups in place for one of the weeks but then setting the other week to a bye week. Here are the steps:

1. Go to League >> Settings >> Edit Regular Season Schedule >> Custom
2. Choose the week you want to make a bye week in the date selector drop-down
3. Drag and drop each team from the left Match-ups column to the "Not Playing" box on the right
4. When the left column is completely empty, click Save at the bottom
5. Inform owners to set their players for both weeks
6. Take each team's final scores from the bye week (these will show up in the "Top Scores" column that appears on the Scores page in the left column of the desktop view) and add them to the final scores for the non-bye week using League >> Settings >> Edit Past Box Score. The win/loss record will then be based on the whole time period using the combined scores.