The January post-holiday slump doesn’t usually make for auspicious Broadway debuts. But that didn’t stop “How to Succeed in Business Without Really Trying” from logging a stellar first week for the show’s new topliner, Darren Criss in Week 32 (Jan. 2-8).“How to Succeed” raked in $1,386,065, and those involved in the show say sales look poised to remain on that level for the next couple of weeks. B.O., aided by Criss’ “Glee” fanbase, also has a sense of urgency, since he will stay for only three weeks before heading back to the Fox skein. Tuner “Porgy and Bess” was one of the few shows to uptick, not least because so many productions had played a sales-boosting ninth perf the previous sesh, and it had not. Also up was “An Evening With Patti LuPone and Mandy Patinkin” ($539,026 for seven shows), on the rise prior to its final full week. There was enough holiday runoff to fuel million-plus sales at eight shows (with “War Horse,” at $999,530, just missing the mark). “The Lion King” began the year at the top of the charts, while the final week of 3-year-old “Billy Elliot” ($1,118,453) helped keep totals high. Otherwise, a number of shows started to feel the downward pull of winter. Overall Broadway cume deflated by $13.7 million to land at almost $24 million for 31 shows on the boards. Attendance was 250,021, vs. 230,000 for 27 shows during the same sesh last year. Along with “Billy Elliot,” the week saw the demise of the short-lived “Lysistrata Jones” ($254,776), which never rallied sufficient biz to stay on the boards. Stepping into the fray was “Wit” ($121,813), playing the first five previews of a Manhattan Theater Club revival starring Cynthia Nixon. The 22 musicals grossed $20,308,646 for 84.8% of the Broadway total, with attendance of 204,146 and an average paid admission of $99.48. The nine plays grossed $3,641,986 for 15.2% of the Broadway total, with attendance of 45,875 and an average paid admission of $79.39.