не про REG_PARSE, а так, для
[VAR][$test][{"image":"data:image\/gif;base64,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","numbers":["82","86","69","23","24"\],"hash":"QWvmgtYNM2t\/KQFDeCp2DrXfuWbGlPUczLfi3Nl5\/xF6ed49FKcDB4h2qvnptxT6hAkrhKQ0vJTmIjhW6SMCdp45rnk3M5IZIUao\/rtjaho="}]
[CLEAR_BUFFER]
[PARSE][numbers":["]["\]][$test]
[SPLIT_STR][","][$1]
[DISPLAY_BUFFER]
[EXIT_TASK]