To edit this source code and make your owen game you should follow just some step
1 open file levelsdata.plist inside resource folder
2 in this file by expanding levels dictionary you can see two dictionary small and big
3 to add more level you just copy small or big dictionary one and past it
4.change name like ("giant" )you want to name of new level
5 expand new create ("giant") dictionary and chafe id value like 3 ( give no of level don't miss this seqavance)
6. for diff size edit size dictionary inside new created ("giant")
7.edit leaderboard id
8. add one text file containing word in project main bundle
9. change value of txtfile in new created dictionary ("giant")
10. compile and run enjoy!!!