So I recently began playing with Mods. After downloading a bunch of different mods, I’ve come across some issues.

1. After leaving Build/Buy mode, my dock disappears (not sure if it’s a called a dock but the thing at the bottom of the screen where you see your Sim and what not). The whole thing just disappears.

2. I’m not able to direct my Sim to do anything (go to the bathroom, eat, nothing).

3. When I’m in Build/Buy Mode: When I try to use the drop down to filter by items, I can only select Holiday Items.

Can someone please help? I love using custom content but it making it harder to play the game efficiently. Please tell when what I’m doing wrong!

You've probably downloaded a broken mod, or didn't get the update of a mod that broke with certain patch
if you know what you've added before it started happening - remove it
if you've updated your game without checking your mods for updates - check them

and for further on always check the dates of any game changing mods* you're downloading
and always check for updates on mods after patch days..

*game changing mods = anything that is not CAS/Build/Buy items
(to those I would refer as CC and they tend to last forever in most cases without the need to be updated on a regular basis, if at all..)

Its probably a user interface mod that's broken. Do you have any CAS Column Mods? CAS Wrench hider mods or even the UI mod that gives you back the old style interface instead of the new bright coloured (horrible and glaring) start up screens. Anyone of those will cause the problem your describing.