@NAPSTER Dont worry about liquidity on listing day atleast. Mostly you should be able to sell like @Vimal Garodia mentioned.
About Groww, Can't recall about pre-open selling. But about Zerodha and HDFC Sec, I can confirm, they do allow. If you are new to IPO market, specially SME segment, I would suggest, go with Zerodha.
In HNI, applying using multiple bids (with same price for every bid but different lot sizes for each bid) - May I know how this would be considered during allotment process ?
Would the application be part of lottery/allotment process for each lot (since 3 bids with different lots are applied) ?