[OOo Calc] Spreadsheet: IF / THEN ?

<Edit> Hello</Edit>

I would like to make a comparison calculation and tried to use an IF(), but I keep getting an error. I use Open Office Calc, here, but that shouldn't matter. What does matter is that I don't know what I am doing with a formula.

I want to compare the elapsed time value in one cell with a new value and, if the new value is lower, to save the new value in the first cell. If the value is equal or > the old value, then I do nothing and move to the next cell.

I can seed the old data column with higher numbers, but it doesn't seem to make a difference,

I was able to use this time format (00:00.000) to do another calculation, so that should be OK.

=IF(C7<E7,C7,E7)

What is wrong? Am I going about this the right way?

I'd also like to find a list of OO.o Calc error numbers and definitions.

<Edit> Thanks in advance</Edit>