To Juozas V:
Thank you very much for this. It does the best English title case conversion that I have seen here.
However, I have one minor quibble. Your word list includes some words and phrases that I see more often used in song titles as subordinate conjunctions than as prepositions. For example "after", "because", and "although". From my reading on capitalization in titles, subordinate conjunctions should always be capitalized. Since it's not practical to use script to detect how a word is used, I chose to remove those words from your Reg Ex on the basis that there should be fewer errors without them than with them. The words that I removed are:
After, As, Although, Because, Even If, Since, Till, Until, When, and While.
Here is my revised word list (resorted alphabetically):
Note that I also added the coordinating conjunction "Nor" to your list.
Doug M. in NJ