This basic script is for people who do not like the look of variables.
All you need to do is change "curr" to your value. The script will do the rest.
In this example, Space increases it by 1, the Right Arrow increases by 100, Down arrow decreases by 100, left arrow decreases by 1. The minimum is 0 and the maximum is 9999.
Based on cpumaster930's version at http://scratch.mit.edu/projects/cpumaster930/2387648