Visualization and visualized meditation

I've come here many times for meditation on the breath. I've come to understand this meditation better, but I encounter problems unrelated to meditation. I've noticed that my memory is rather bad, and that my thought process relies mostly on verbal means. However, I remember being extremely visual at an early age, scoring quite well on visual aptitude tests, and these days I can sometimes visualize complex things. Yet, I fail to use visualization in every day life because I understand Buddhism discourages mental fabrication. I am thus very focused on exterior reality, either sensing reality or thinking abstractly. I'm wondering if visualization meditation would help me with memory and conceptualizing. I must also mention that I have a mood disorder, and though I doubt visualizing could affect this, I am still worried of the possibility. Thus, my questions are: 1. Is intentionally visualizing something very different from fantasies discouraged in Buddhism? 2. Is visualizing generally different from engaging in visualization in meditation? 3. Are there any risks involved in visualization practices, in visualization as a general trait of mind? 4. Would visualizing improve memory, retention, or modelling? 5. Could visualizing in a free and unrestricted way liberate or affect emotions, undo repression? I am thankful for any replies.