Whilst browsing the level solutions page I noticed something strange, perhaps someone can explain this to me.
My solution to level 34 - Quickly, has been beaten (no problem there, I never expect them to last!). It's a simple solution, however, probably the same as most people's, consisting of a single metal bar. The budget is $29 so there's $19 left. However, the new top score saves an extra dollar, finishing with $20 left. No problem there, except the solution is identical. Clicking "clear" shows that the initial level budget here was $30, not $29.
Where did the extra dollar come from? Have the built-in levels been changed in more recent versions of the game? Some kind of hack, or just a mysterious bug? Anyone noticed this with any other levels?