It would certainly be happier to live outside when temperatures are above 40F. Introduce it to full sun slowly and gradually so the leaves do not scorch. A good time to do that is when there is stretch of cloudy rainless weather. After it rains, if you get summer rains, tilt the water out of the center of the plant, or blow out the water with a drinking straw. If your summers are hot and humid, watch it on watering.

If you water as soon as top 1-2" are dry, maybe it is too soon - depending how well soil drains. If it contains too much peat, that could be staying too wet for too long. Check deep inside of pot (at least 2/3 deep or even deeper), using a bamboo/wooden skewer, chopstick, dowel with sharpened end or even pencil.

Can't really tell for sure looking at the photo, but that leaf may be waterlogged? Is it too soft? You said bottom leaf rotted - that is why I suspect soil to be water retaining.

I’m wondering about the cactus mix you used. It looks more like regular garden soil.

Hello, what kind of soil did you use? Also in the future only repot when they are in the growing season. Aloe's like to be root bound and do not require a large pot. The larger the pot the more the soil retains water and can lead to root rot. I only water my Aloes about one time a month in winter, then every 2 weeks in summer. Aloes retain water very well in their leaves and need a lot less water than people think. I keep mine in a south facing window where it gets direct sun in morning. Sometimes their leaves will do weird things, but that doesn't necessarily mean something is wrong. Just be very careful with watering and only water it when the entire pot of soil is dry. You can never hurt it by under watering, but Aloes are prone to root rot with too much water. It doesn't look bad to me in the pictures, just give it some sun and let it dry put completely.