If really damaged, then your phone will not be able to read any sim card.

If sometimes fail to read, then you need to check and test whether it's the sim card or the reader problem.
Maxis is RM25 if not wrong, but not sure how my friend got it for FREE, possible because he took up the plan with phone which require micro-SIM.

Adapter won't damage the micro-SIM, UNLESS maybe you bent the micro-SIM when trying to fit in the adapter?
Another issue you need to worry is those phone which use SLIDE-IN and click type SIM, if you're using adapter which does not hold the micro-SIM properly (usually DIY one using tape), your SIM card might get stuck and risk to scratching the reader part if you force it in or out.
No need. Just go to Telco and request to change to micro-SIM, will charge you a little.

Telcos in shopping malls opens everyday including weekend. (e.g. Sunway Pyramid)
Yes, definitely. CUT means not proper, just like if you cut-and-join wires. Though, not everyone face problems, only those unlucky ones, similarly, cut-and-join wires also not everyone have problem. But why cut when you can replace easily and at very little cost? Unless it's emergency or temporary.
So, the better advice is surely to use a proper one than cut, after all, cutting involves risk.
Some people, after they cut, they keep the left-over to be use as adapter, but it's not advisable IF you're using the micro-SIM on those SLIDE-in-out and click type SIM phone. Nonetheless, even you cut the micro-SIM, you notice that the edges may be sharp and unevent, so there's also risk when you slide the micro-SIM inside the Lumia or those micro-SIM phone which requires sliding the micro-SIM in and out. Another problem is the micro-SIM may be slightly bent and eventually the micro-SIM failed. It may not happen immediately and don't know when will happen.  If you're really unlucky, and the micro-SIM fail when you have something really important... then how? E.g. emergency situations, the micro-SIM failed! I know not many people are unlucky people, so they may not able to imagine these situations, but for those who often faces unlucky situations, they will understand and easily imagine all sorts of conditions.

Nokia 808 Pureview @ Long Exposure shot by JTproductions, on Flickr


Nokia 808 Pureview @ Long Exposure Shot by JTproductions, on Flickr


Nokia 808 Pureview @ Long Exposure shot by JTproductions, on Flickr


Nokia 808 Pureview @ Orange Dragonfly by JTproductions, on Flickr
Nokia 808 Pureview @ Orange Dragonfly by JTproductions, on Flickr

Nokia 808 Pureview @ KLCC by JTproductions, on Flickr


Nokia 808 Pureview @ KLCC by JTproductions, on Flickr


Nokia 808 Pureview @ KLCC Light Painting by JTproductions, on Flickr


Nokia 808 Pureview @ KLCC by JTproductions, on Flickr


Nokia 808 Pureview @ Light Trails by JTproductions, on Flickr

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