1. Normally the cheque will be paid in favour of the vendor, unless the vendor instructs it to be paid in favour of the lawyer, perhaps to contra with legal fees.
2. As stated above, normally it will go to the vendor.
3. Normally in the Letter of Offer to Purchase, a time frame will be given to the purchaser to sign the SPA. Normally it would be 14 working days. If the purchaser delay, the 2% earnest deposit is forfeited by the vendor as compensation. Alternatively, the vendor can sue the purchaser to compel him to proceed with the SPA and complete the transaction.
4. Depends on what is stated in the SPA. If it is silent, vendor can have the deposit, but he must be vary that if consent is not allowed (I'm assuming that's what you meant by 'approved by pejabat tanah') - then the vendor must refund the deposit.
5. No. Once the vendor has accepted the earnest deposit and executed the letter of offer to purchase, that is consideration moving from the purchaser to the vendor. It is a binding contract. The purchaser can sue the vendor to compel him to proceed with the SPA and complete the transaction.