I would recommend also checking out the True Dungeon forums. There are resources for generalists as well as class-specific.
Going beyond the podcast information, there were a couple areas where additional clarification is needed:
First: It is important to distinguish the types of runs
*"Standard runs" - these are the season specific ones and will be detailed in the description that it is part of a longer story arc. These are the typical runs average fans do. There used to be puzzle or combat focused runs but that has changed starting this year where different destinations can happen based on your choices and preferences. N1-N3 are the standard runs this year. These combine puzzle solving with ability to handle combat, etc.
*True Grind - This year, it is called Pandemonium and Back. Grind runs are designed for experienced players with substantial investments made in their character builds. Do not start with one of these - they are focused on combat and really testing the mettle of serious players. They are fun but not the best to start with - they are a combination of combat and tactics.
*"Sealed Pack" or "Sealed Ticket" runs - These are runs where you get the standard 10 pack of random tokens for each player and, as a group, you come up with a party. You can't bring anything there to use so it is all about making due with what appears. These are a combination of puzzle and combat rooms. This year's Viper's Pit is an example of this (it is a redesigned version of a 2014 run).
Second: Difficulty levels
Difficulty levels are decided by the group - the easiest level voted is what the group does. Don't make the runs too easy if you can avoid it - especially if experienced players are there to help you.
*non-lethal and normal - These levels are designed for beginners or really passive players. If you didn't bring any tokens and use what they hand you - you should be able to beat a run on normal most of the time. Non-lethal is generally used for younger audiences or those feeling really afraid of taking this on. As a general rule, if you have even 2-3 people who have ever done it before - don't make them do non-lethal.
*Hardcore - Technically, you can beat hardcore with 10 packs but it will be really hard and you'll likely not win. 2 players with ultra-race (purple) in half their slots can beat a hardcore run by themselves. Only take this on if you have experienced support. As an aside, you almost never see anything less than hardcore being run on Grinds.
*Nightmare - Designed for experienced players. You'll need a party with quite a few UR items and experience in order to have a good shot. 2-3 people running all UR and a good deal of legendary tokens can beat a nightmare run on their own but won't win every time.
*Epic - Designed for those who want to take a beating. Don't request this unless you are extremely experienced and routinely beat nightmare levels.
A good comment from the podcast was about being able to run on normal without additional tokens. If you get hooked, gradually build up your collection - focusing on the classes you enjoy the most. Before you put down $100+ for Ultra-rare tokens, get to where you have a good set of rare and uncommon items for your specialty class - typically possible for $40-$50. One thing to note is you want treasure enhancers as soon as possible - even if it only adds 1 more treasure. The tokens you pull in treasure boxes at the end of adventures are significantly better than the random 10 packs. If you pull a purple print token (ultra-rare), reserve gold bars, wish rings, green backed tokens (legendary or premium tokens) - you can either build around one of those initially or go to the True Dungeon forums and you can find good trades to build up leveraging the initial token as a starting point (don't just take the first offer - even post what you were offered in your thread (without names) to make sure you are getting a good deal). The token stores like Trent's tokens or TD Tavern are a good place to get baseline prices those tokens are worth. Valuable tokens can range from $100-$125 for this year's ultra-rares to over $1,000 for legendary items.
Last note: Combat efficiency
Combat efficiency is important. You have limited time to defeat creatures - the more slides you do, the more damage you do. Decide order for sliding (which players go first) then slide and quickly move to the side to let your friends take their shots. If you don't know the symbols, etc for spells - just tell the DM that you fail the test quickly - it only means a small reduction in damage. Between all of that, you can increase your combat capability by 20%-30% - sometimes making the difference between winning or losing overall.
Hopefully this helps!