Hopefully, the answers below will address your questions...
1. What does Style pattern really do here? How does it determine which box pattern goes to which box! Graphdata1 means first First Bar in Graph?
Answer: When a discrete attributes map is not used, the first-occurring group value is assigned to the first part, the second value to the second pattern, etc.
2. To make the whiskers to be solid, set WHISKERATTRS=(PATTERN=1) on the BOXPLOT statement.
3. To make one legend with three entries, you will need to strip the "-<region>(n-<N>" from you group values. Then, the legend will naturally return to type-only entries
4. The AXISTABLE code looks correct. Are your "n" values correct?
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