If it's just short of RM600, ask your brother or your wife to borrow less RM600 la. Why want to tie you for 30+ years just because of the RM600 difference **cannot brain**

Guarantor is as good as being a borrower because you are in the contract with the Bank. A Guarantor's position is no different in the sense that if the borrower fails to pay back the monies borrowed, the Guarantor guarantees to pay on behalf of the borrowers. If at all you want to know the difference then this is it, the guarantor bears liabilities but no benefits. Money goes to the account of the borrower but nothing goes to the guarantor.

If the loan becomes an un-performing loan then you'll be deemed as a defaulter as well and yes, you're credit report will be affected.
Yes. In fact, a Guarantor can be sued bankrupt for monies he/she did not borrow. The recent amendment to the Bankruptcy Act however now provides for a method for guarantors who are made bankrupt in the capacity of a guarantor to discharge themselves.

it depends on the banks. Some banks will claim that they are asking for a guarantor but it will appear in the guarantors CCRIS report as a joint borrower. You would want to avoid this.

The traditional way is that the guarantor will not have his/her ccris affected in any way, unless the borrower defaulted on the payments
it depends on the bank actually, some will let you know upfront that being a guarantor would affect your CCRIS. ideally you would like to avoid this.