1)&2) Bond always being redeemed at face value, disregard the market price.

3) Yes, but market generally taking into account already, the bond won't be traded at Rm90, if it is going to be matured tomorrow.
Who is the water fish to sell at Rm90, when tomorrow can get Rm100? 
Unless there is a risk of default.
Single tier system already in place many years back.

Old imputation dividend system is going to be obsolete next year. In other word, start next year, all dividend is under single tier.
Those tax credit under old imputation system will be obsoleted.