Just trying to read the recipe easier, hope you don't mind...  Please correct the cup sizes if your cup is different.

Basic white bread:

                  Small                                          Large
Water         3/4 cup               178g            1 1/8 cups     266g
Skim milk pwd 2 tbsp                                2 1/2 tbsp
Butter        2 tbsp                                        2 1/2 tbsp
Sugar         1 1/4 tbsp                                  2 1/4 tbsp
Salt            1 tsp                                             1 1/4 tsp
Strong white flour 2 cups      250g            3 cups            375g
Dry yeast    1 tsp                   3.3g               1 1/4 tsp



So with using one or the other recipe we have 71% hydration based on a 125g cup of flour & 237g cup of water.   Yeast is just under 1.4% of the flour.

That would be a lightly spooned and leveled dry measuring cup.  One difference could be a heavy measured cup, with the powdered milk making a firm dough.  Why bread flour is used is beyond me, try mixing half bread with all purpose flour and see what happens.  (only make one change at a time with each bake) (first loaf)  My thoughts are that 71% hydration is rather wet but adding the bread flour weight (130g cup) brings it down to about 68% and the powdered milk soaks up water as well so it is more in the neighborhood of 66%.  The texture you describe does sound wet, how was the sliced bread moisture?

The yeast seems a bit much to me and increases a whole gram more than the 1.4% with the larger recipe.  Dough machines are sensitive to too much yeast a very common problem with bread machines.   Very often only a reduction in yeast solves the problem.   Is there a way to watch the dough rise through a window?  If so take notes and watch the dough rise and fall during the process.  If the bread is baked after it has fallen and there seems to be no time for it to recover, then there is too much yeast and amount needs to be reduced.  Reduce yeast as a second correction (second loaf) to see what happens keeping all of the bread flour.   If the loaf improves, then try using reduced yeast with half bread half all purpose flour (third loaf) to see if it improves further.

By the way, did you try the small or the large recipe?  

Try also reducing the sugar in a loaf to just a teaspoon per cup of flour or eliminate it altogether.  (fourth and fifth loaves)  Make comparisons to the other loaves.

Have fun wearing out the machine,  Mini  :)