Some problems found with user macros:

1. host and template level macros:

• some macros can disappear at their saving; how to repeat a problem:
  a. add two macros {$A} and {$B}
  b. remove macro {$A}
  c. add macro {$C} and save host or template
  d. only {$C} macro will be saved

2. template level macros:

• the distance between macros isn't enough (see a screenshot)

3. the source code for template/host and global level macros is very different; it should be unified

4. the validation order of macros isn't logical

5. in API there aren't some checks

• a check for duplicated macros

6. error messages violates coding style; for example:
frontends/php/api/classes/class.cusermacro.php:735, 738