In
another thread the limesurvey invernter/developer said:
"The process of adding new questions is very complicated. For me, even having created the software and knowing the general systems behind it, it takes, on average, 10 hours - and then often requires significant debugging once follow-on issues start to arise.
You'll need to make modifications in at least the following files:
common.php
qanda.php
activate.php
browse.php
dataentry.php
export.php
spss.php
questionhandling.php"
Implementing a new question type is really hard. For you the easiest way would probably be to donate and ask an experienced programmier to do this for you. There are so many files and dependencies you have to take care of.
If you really want to try implementing a new question type here are some more links which might be helpful:
-
How to join the LimeSurvey Project Team
-
Accessing the Source Code
-
Coding Rules
-
LimeSurvey 1.53 Database Layout Documentation
Ondersteuning 
