Steve,
I would say that there are three potential issues here. I will list them in the order from most probably to least, and will give you preventative measures for those that have the option to:
1.) You put it in the shade: Junipers, and really conifers in general, love full sun. In fact, if a juniper doesn't get full sun over the course of a few years, you can visibly see a difference in strength, vigor, and color. It's not that bad of an idea to keep it in partial sun right after the repot, especially if you are in a really warm climate, but you shouldn't wait more than a week to get it back out into full sun. Get it out into full sun as soon as possible.
2.) Treat for Mites: It is quite possible that the tree is infected with Spider Mites, especially if you kept watering the same amount when the tree was in the shade. Go to your local nursery and buy horticultural oil. It is stronger than Neem Oil. This will will the spider mites and also kill any eggs they have laid on the tree. Please note: For a day or two after you apply the oil, keep it out of the sun, as Horticultural Oil in full sun will burn the foliage. Follow the label in regards to how long you need to keep the application on for it to be effective, and then water the foliage with a strong enough flow to remove the oil from the foliage.
3.) Juniper Branch/Tip Blight- This is a fungus, I believe (If I am wrong someone step in and correct me), which occurs when there is too much moisture in the canopy of the tree. Typically this is caused by overwatering, but it can also occur because the tree is near other specimen that are infected with it. For this, you can use Mancozeb. Please read the label and research online for the correct dilution ratios. I have not been able to find a pre-mixed solution, and really you want to be able to control the amount in your solution. In addition, remove all yellow, potentially infected tissue.
Try to fix these three issues in order. See how it responds to full sun and check for mites. You can typically see them on the foliage. Where I live, they are red little spider mites. I have also seen white spider mites. If you can see mites, go ahead and treat that right away. If the full sun and spider mite treatment doesn't stop the decline of the tree, go for the Mancozeb option. I hope your tree survives. It really has a great branch structure. Make sure you are watering enough but not too much. When a tree is freshly repotted, it takes awhile before it begins absorbing water like it did before the root work. You can see it happen over time with how quickly the soil dries out.
