I am assuming that you are referring to using midupdate.tcl to set the market id, correct? Here's the info I found on setting up your locals market id using midupdate.tcl with xPlusz included in SuperZap's 2.5.2 upgrade:
Local guide data tends to get lost due to various issues regarding bin changes, software updates, etc, etc. Here is a list of steps to take when that happens. I realize that many have come up with variations of these steps and others that work for them. My response to that is.. if it works for you do it! The below is meant as a guide for those who have tried everything else with disappointment. The below, if followed to the letter takes some real time and effort but it is a sure fire method when guide data goes away. I would highly recommend the prerequisites as I feel fairly certain you won’t regret it. Total time including perquisites should be no longer than an hour.
GUIDE DATA POPULATES IMMEDIATELY
PREREQUISITES (a and b)
a) HU Card needs to be set up for locals with correct zip code (listed below) and whatever else your software allows you to set.
b) Use the Xupdate.zip found at
http://www.pitoudistro.com/pd/xtreme.html to upgrade your Tivo software to 2.5.2.
(Even though your software may already be there, this is EXTREMELY important because Xtreme contains many hacks, command line utilities, and etc that will make your life SO much easier if you will just do it. It is really pretty simple. Just burn and boot to the CD created by using the ISO image contained in the xupdate.zip file above and follow instructions. Put the drive back in the Tivo and you are in business.)
STEPS TO TAKE
1) Once Tivo comes back up, RESET all locals by running Xtreme's Xpluz command #61 (Xpluz is already installed with Xupdate and descriptions of how to run these commands is in the readme for Xupdate.)
2) Reboot the reciever (USING the Tivo remote control) and verify that all locals are gone! If you only run midupdate.tcl without resetting (#61), the guide data does NOT GET POPULATED.
3) Copy midupdate.tcl to /var/hack folder created by the Xtreme software and do a "chmod +x midupdate.tcl" to make it executable.
4) From the bash prompt (/var/hack#), type "tivosh ./midupdate.tcl XX" (XX is the number designated for your Market ID found in the “listing of codes” below and other lists like it)
YOU SHOULD NOW SEE LOCALS POPULATING ALMOST IMMEDIATELY (Within 2 Minutes)
Population will be TEMPORARY without step 5.
5) Then #60,XX (XX is the Local Code EXAMPLE: Commands for Atlanta listed below would be "#60,1" and Baltimore would be "#60,1A")
LISTING OF CODES:
#Hex,Decimal,City,State,Zip Code,Sat,MarketId
#01,001,Atlanta,GA,30301,101,10
#19,025,Austin,TX,78701,119*,12
#1A,026,Baltimore,MD,21201,119*,14
#1B,027,Birmingham,AL,35201,119*,22
#02,002,Boston,MA,02101,101,25
#1C,028,Charlotte,NC,28201,101,35
#03,003,Chicago,IL,60601,101,39
#1D,029,Cincinnati,OH,45201,101,41
#04,004,Cleveland,OH,44101,101,43
#1E,030,Columbus,OH,43201,101,48
#05,005,Dallas-FT. Worth,TX,75201,101,51
#06,006,Denver,CO,80201,101,54
#07,007,Detroit,MI,48201,101,56
#1F,031,Greensboro-Winston Salem,NC,27401,119*,79
#16,022,,,,,81
#08,008,Houston,TX,77001,101,90
#20,032,Indianapolis,IN,46201,101,93
#21,033,Kansas City,MO,64101,119*,100
#09,009,Los Angeles,CA,90001,101,113
#22,034,Memphis,TN,38101,119*,121
#0A,010,Miami-FT. Lauderdale,FL,33101,101,123
#23,035,Milwaukee,WI,53201,101,124
#0B,011,Minneapolis-St. Paul,MN,55401,101,125
#24,036,Nashville,TN,37201,101,132
#0C,012,New York,NY,10001,101,134
#0D,013,Orlando-Daytona,FL,32801,101,140
#0E,014,Philadelphia,PA,19101,101,147
#0F,015,Phoenix,AZ,85001,101,148
#25,037,Pittsburgh,PA,15201,119*,149
#26,038,Portland,OR,97201,101,150
#17,023,,,,,155
#10,016,Sacramento-Stockton,CA,95201,101,163
#18,024,Salt Lake City,UT,84101,101,165
#27,039,San Antonio,TX,78201,119*,167
#28,040,San Diego,CA,92101,119*,168
#11,017,San Francisco-Oakland-San Jose,CA,94101,101,169
#12,018,Seattle-Tacoma,WA,98101,101,172
#13,019,St. Louis,MO,63101,101,182
#14,020,Tampa-St. Petersburg,FL,33601,101,185
#15,021,Washington DC-Hagerstown,MD,20001,101,199
#29,041,West Palm Beach-FT. Pierce,FL,33401,,202
Other lists with more cities can be found hiding in various other posts.