Trouble transcribing this bar (easy question)

Hello, I'm trying to transcribe this song:

http://www.scribd.com/doc/55177619/John-Legend-So-High-Sheetzbox

I'm doing okay with it, but sometimes there are too many notes in one bar, and Musescore won't let me insert them.

For example: [if you look at the 4th Bar, on Line 2] you will notice there is a dotted minim [on G]. Musescore doesn't allow me to insert this without deleting other notes to fit into the 4/4 time signature.

Is there a way around this?

Another example is the 1st Bar on Line 3. There are two semibreves in the bar, yet there are still other notes that fit in the bar. How can this be if a semibreve takes up 4, how can I insert all these notes?

I really hope there is a way. Thanks for reading and if you can help I would be eternally grateful.